The present disclosure relates generally to medical devices and methods, and more particularly to systems and associated methods for manipulating or retracting tissues and anatomical or other structures within the body of human or animal subjects for the purpose of treating diseases or disorders.
One example of a condition where it is desirable to lift, compress or otherwise remove a pathologically enlarged tissue is Benign Prostatic Hyperplasia (BPH). BPH is one of the most common medical conditions that affect men, especially elderly men. It has been reported that, in the United States, more than half of all men have histopathologic evidence of BPH by age 60 and, by age 85, approximately 9 out of 10 men suffer from the condition. Moreover, the incidence and prevalence of BPH are expected to increase as the average age of the population in developed countries increases.
The prostate gland enlarges throughout a man's life. In some men, the prostatic capsule around the prostate gland may prevent the prostate gland from enlarging further. This causes the inner end of the prostate gland to squeeze the urethra. This pressure on the urethra increases resistance to urine flow through the end of the urethra enclosed by the prostate. Thus the urinary bladder has to exert more pressure to force urine through the increased resistance of the urethra. Chronic over-exertion causes the muscular walls of the urinary bladder to remodel and become stiffer. This combination of increased urethral resistance to urine flow and stiffness and hypertrophy of urinary bladder walls leads to a variety of lower urinary tract symptoms (LUTS) that may severely reduce the patient's quality of life. These symptoms include weak or intermittent urine flow while urinating, straining when urinating, hesitation before urine flow starts, feeling that the bladder has not emptied completely even after urination, dribbling at the end of urination or leakage afterward, increased frequency of urination particularly at night, urgent need to urinate etc.
In addition to patients with BPH, LUTS may also be present in patients with prostate cancer, prostate infections, and chronic use of certain medications (e.g. ephedrine, pseudoephedrine, phenylpropanolamine, antihistamines such as diphenhydramine, chlorpheniramine etc.) that cause urinary retention especially in men with prostate enlargement.
Although BPH is rarely life threatening, it can lead to numerous clinical conditions including urinary retention, renal insufficiency, recurrent urinary tract infection, incontinence, hematuria, and bladder stones.
In developed countries, a large percentage of the patient population undergoes treatment for BPH symptoms. It has been estimated that by the age of 80 years, approximately 25% of the male population of the United States will have undergone some form of BPH treatment. At present, the available treatment options for BPH include watchful waiting, medications (phytotherapy and prescription medications), surgery and minimally invasive procedures.
For patients who choose the watchful waiting option, no immediate treatment is provided to the patient, but the patient undergoes regular exams to monitor progression of the disease. This is usually done on patients that have minimal symptoms that are not especially bothersome.
Surgical procedures for treating BPH symptoms include Transurethal Resection of Prostate (TURP), Transurethral Electrovaporization of Prostate (TVP), Transurethral Incision of the Prostate (TUIP), Laser Prostatectomy and Open Prostatectomy.
Minimally invasive procedures for treating BPH symptoms include Transurethral Microwave Thermotherapy (TUMT), Transurethral Needle Ablation (TUNA), Interstitial Laser Coagulation (ILC), and Prostatic Stents.
The most effective current methods of treating BPH carry a high risk of adverse effects. These methods and devices either require general or spinal anesthesia or have potential adverse effects that dictate that the procedures be performed in a surgical operating room, followed by a hospital stay for the patient. The methods of treating BPH that carry lower risks of adverse effects are also associated with a lower reduction in the symptom score. While several of these procedures can be conducted with local analgesia in an office setting, the patient does not experience immediate relief and in fact often experiences worse symptoms for weeks after the procedure until the body begins to heal. Additionally all device approaches require a urethral catheter placed in the bladder, in some cases for weeks. In some cases catheterization is indicated because the therapy actually causes obstruction during a period of time post operatively, and in other cases it is indicated because of post-operative bleeding and potentially occlusive clot formation. While drug therapies are easy to administer, the results are suboptimal, take significant time to take effect, and often entail undesired side effects.
There have been advances in developing minimally invasive devices and methods for lifting and repositioning of tissues. However, further advances are necessary to ensure an ability to access difficult to reach body structure.
There remains a need for the development of new devices and methods that can be used for various procedures where it is necessary to employ flexible or versatile devices for accessing target anatomy and minimizing patient discomfort. Changing the flexibility of interventional devices and maintaining positioning with respect to anatomy may additionally be necessary. In particular, there is a need for alternative apparatus and treatment approaches for the purpose of engaging or reaching anatomy from various angles. An ability to access anatomy with minimally invasive instruments while viewing the interventional procedure is also desirable. Moreover, various structures ensuring an effective interventional procedure such as implants having structural memory characteristics have been found to be helpful in certain treatment approaches.
The present disclosure addresses these and other needs.